Phytomyza dalmatiensis

Phytomyza dalmatiensis (Spencer, 1961)

on Clematis

mine

The mine begins with a lower-surface, more or less contorted, epidermal, silvery corridor with a fine black frass line. Then follows an upper-surface, shallow, not much contorted corridor that, especially in larger leaves, follows the leaf margin over long stretches. Sides rather straight. Frass in long strings, often over long distances at one side of the corridor only. Pupation outside the mine, exit slit now upper-, then lower-surface.